Third-Party PLX8747 NVMe Card Identified as "HP Z Turbo Quad Pro" on Z820

[Kakirman]

Hello everyone,

I'm writing to share an interesting discovery regarding a third-party NVMe card on the HP Z820, which I hope will be useful to others.

I recently purchased a quad-slot NVMe PCIe card featuring the PLX8747 chipset. My primary intention was to use it in my Mac Pro 7,1 (2019), as official options like the OWC cards are quite expensive. The card cost me the equivalent of about $100 USD Amazon  

After testing it on the Mac Pro, I decided on a whim to see how it would perform in my HP Z820 workstation.

Test Setup & Performance:

• Workstation: HP Z820

• Drives: 4x 512GB Kioxia XG8 NVMe SSDs (Part #: KXG80ZNVG)

• Single Drive Performance (Z820): I benchmarked a single drive and achieved speeds around 3,500 MB/s, which is expected given the limitations of the Z820's PCIe 3.0 interface.

• RAID 0 Performance (Z820): I then configured all four drives in a RAID 0 array. However, the performance was underwhelming, not exceeding 4,500 MB/s.

• RAID 0 Performance (Mac Pro 7,1 - PCIe 4.0): To confirm the card's full potential, I moved the same RAID 0 array back to the Mac Pro. The results were phenomenal: ~13,400 MB/s read and ~8,863 MB/s write. This confirms the card itself is highly capable.

The Surprising Discovery:

Now, for the main point of this post. I accidentally stumbled upon something fascinating. When I opened HP Performance Advisor on the Z820—with all four NVMe SSDs installed—I was shocked to see the card identified in the Block Diagram for PCIe3 Slot 6 with the label: "HP Z Turbo Quad Pro".

I rebooted the machine to double-check, and the configuration remained the same. It seems the system properly identifies the card as an 'HP Z Turbo Quad Pro' only when it is populated with all four NVMe drives.

This is particularly surprising because, as many of you know, most standard Z Turbo cards (especially the smaller, single-NVMe versions) often do not work in the Z820 without physical modification. I personally had to return one of these smaller Z Turbo cards in the past because it was not detected.

Conclusion:

In summary, it appears that quad-NVMe cards based on the PLX8747 chipset work flawlessly in the HP Z820, including full support for PCIe bifurcation. While you will be limited by the PCIe 3.0 interface speeds, it's a fantastic and affordable way to add high-capacity, fast storage to these aging but still incredibly capable machines. It's truly great to see these workhorses get a new lease on life.

Links to the Card:

Here are links to the card I purchased for reference.

Turkey Link 

Ebay Link 

I have attached screenshots of my performance tests and the HP Performance Advisor diagram below.

Hope this helps someone!

(Test Screenshots Attached Below)

[DGroves]

i suspect the HP performance advisor is coded to say HP Z Turbo Quad Pro for any quad based SSD using a PLX8747 switch chip which is primarily used for video based products but is equally happy for use in just about any high speed data xfer based task

such as this one as a example

https://www.amazon.com/Generic-Adapter-PLX8747-Profile-Support/dp/B0CXX88FZD

PLX8747 data sheet

https://docs.broadcom.com/doc/12351854

last, the single SSD slot pci-e based "turbo Z" cards are completely different in circuitry from the dual/quad card

the single "turbo z" cards are just dumb generic PCI-E to M.2 adapters using a custom reset line modification circuit on the card to lock the card to specific HP workstation models and a circuit to allow each card to have a different device ID for multiple card use

Edit: forgot to say thanks for the speed benchmarking information on the z820 pci-e 3 vs mac pci-e 4 very useful real world comparisons

[SDH · Accepted solution]

Welcome to our friend from Türkiye,

Also, the Z820 BIOS does not support true bifurcation, which is splitting up the electrical lanes of a PCIe slot into true units of 4 separate electrical lanes, each unit functioning at full bandwidth simultaneously. A M.2 NVMe drive needs 4 separate electrical lanes to function at full bandwidth. In a x16 PCIe slot this could more accurately be termed "quadrification" to run 4 M.2 drives via a single x16 PCIe card, the Z Turbo Drive Quad Pro. "Bifurcation" is accurate in the context of a x8 PCIe slot in which the Z Turbo Drive Dual Pro can be used to support full bandwidth for two M.2 NVMe drives simultaneously.

The first family of HP workstations that received the BIOS capabilities of bifurcation was the Z440/Z640/Z840 and these are particularly nice HP platforms to soup up now at low net cost by recycling via eBay because they are currently the third generation back from the latest.

[Kakirman]

@DGrowes and @SDH

Thank you both for the incredibly insightful and detailed replies! I sincerely appreciate the warm welcome and the excellent technical clarifications.

Your explanations have perfectly cleared up the "mystery." I now understand that the magic behind this setup is not the Z820's BIOS supporting bifurcation (which, as you correctly pointed out, it does not), but rather the PLX8747 chip on the card acting as a PCIe switch.

This is a crucial distinction. The switch on the card itself manages the distribution of the PCIe lanes to the four NVMe drives, making the motherboard's lack of native bifurcation support irrelevant. The Z820 simply sees a single, complex PCIe device, and the switch handles the rest.

The theory that HP Performance Advisor is simply identifying the PLX8747 chip and applying a known label like "HP Z Turbo Quad Pro" also makes perfect sense. This, combined with the explanation of how single "dumb" Z Turbo cards have different proprietary circuitry, explains why they often fail where this card succeeds.

This has been a fantastic learning experience. The key takeaway for other Z820 users is now even clearer: if you want to run multiple NVMe drives from a single slot, you don't need BIOS bifurcation support, but you absolutely need a card with an onboard PCIe switch like the PLX8747.

Thanks again for sharing your expertise and helping to make this a very valuable thread for the community!

[SDH]

Kakirman, 

Happy to help.

I'm curious... what is your boot/applications drive? I'm sure you know that the ZX20 workstations don't contain BIOS code to allow them to boot from a NVMe drive. HP engineered the Z Turbo Drive (the v2 version with the excellent heatsink is best... see the ZTD Secrets post HERE ) but the ZX20s can only boot from two special AHCI-controller M.2 drives... not common NVMe-controller M.2 drives. DGroves and I have both done speed testing, and the special (less common, second released) HP AHCI-controller Samsung SM951 can indeed come very close to full NVMe-controller M.2 speeds.

However, the largest size of those SM951 M.2 drives is 512GB. More recently I've worked on a project to get OPROM-supplemented drives to work in the ZX20 workstations. You can find that detailed post here by searching the forum for OPROM or use the link HERE . Via a single BIOS change from "Factory Defaults" even larger and faster NVMe drives can be used for boot/ applications/ storage. The "OPROM" boot code is donated from the drive's controller over to the ZX20 during boot automatically when that BIOS switch is turned on, and NVMe boot can then proceed.

The two drives I've focused on are the M.2 Samsung 950 Pro (but that also has a max size of 512GB) run from a ZTD G2 and the Intel Data Center P3700 (which is very fast, has exceptional longevity, and is a PCIe x4 add-in card). If you review that post all the details are there. These drives should be firmware updated to the latest and GPT partitioned for best UEFI functionality (easy to do). The Intel P3700 cards are available recycled via eBay for very reasonable cost. I'm using the 800GB version but could go up to 2GB if needed. We only use ones originally straight from Intel (very easy to firmware upgrade), but other OEM ones with OEM firmware are hard to upgrade. I explain how to only get the non-OEM ones coming with the Intel firmware and provide the correct software link and HowTo.

If your boot drive currently is a SATA SSD there is room for a very big improvement... and if it is a SATA HDD there is room for a huge improvement. I'm running these under W11 24H2 installed via Rufus 4.9, and the Intel P3700 is working perfectly in our Z620 workstations. It will work in the Z420 and the Z820 just as well.

Works in Z420/ Z620/ Z820

[Kakirman]

Thanks a lot for this incredibly detailed and insightful response. I really appreciate you taking the time to share this valuable information.

​You are absolutely right about the Z820's lack of native NVMe boot support. I'm quite familiar with this limitation and had previously experimented with it, successfully enabling NVMe boot using the Duet/rEFInd method. For my current daily use, I've simply opted to boot from a SATA SSD for convenience, while using the NVMe array for high-speed storage.

​The OPROM method you've described is fascinating and an excellent piece of information. I was not aware that certain drives like the Samsung 950 Pro or the Intel DC P3700 could provide their own boot code to the Zx20 BIOS with a simple settings change. That's a much more elegant and "native-like" solution compared to the workarounds I've used.

​Thank you especially for the links to your detailed posts. I will definitely be reading through them. It’s a fantastic solution for anyone wanting a direct NVMe boot experience on this hardware.

​My primary goal with the PLX-based quad card was to add a large, high-speed storage pool for my projects, and it’s great to learn there are these elegant solutions for the boot drive itself.

​Thanks again for sharing your deep knowledge. This is the kind of information that makes these communities so valuable for keeping these powerful workstations alive and kicking!

[Kakirman]

The message is duplicated for some reason. Could the moderators please delete my duplicate answers? Including this message.
Thank you very much...

[Kakirman]

The message is duplicated for some reason. Could the moderators please delete my duplicate answers? Including this message.
Thank you very much...

[DGroves]

there are other tweaks/improvements that are worthwhile on the z820 either read my previous posts on the z820 or "PM" me

[Kakirman]

Thanks @DGroves 😊

I’d like to contribute an additional piece of information to our discussion on expanding the Z820's storage capabilities. Further to my tests with the PLX8747 card, I've now had the chance to evaluate a different, more affordable quad NVMe adapter.

This new card is built around the ASMedia ASM2824 PCIe switch chipset. A few key differences from the PLX card are its lower price point (I acquired it for approximately $70 USD) and its requirement for an external SATA power connector, presumably to ensure stable power delivery to all four drives. I have also observed that it tends to generate a fair amount of heat, so good case airflow is recommended.

Testing and Outcome:

I installed the card in my HP Z820 and populated it with two NVMe SSDs for an initial test. The system booted without issue, and the operating system immediately recognized both drives.

The crucial finding is that, similar to the PLX8747, the ASM2824 chip functions as an onboard PCIe switch. It presents a single endpoint to the motherboard and manages the "bifurcation" internally. This effectively circumvents the Z820 BIOS's lack of native bifurcation support, allowing all installed drives to be addressed independently.

While I have yet to run performance benchmarks with all four slots filled, this initial test confirms that these ASM2824-based cards are fully functional in the Z820. For users seeking a lower-cost entry point for adding a high-capacity NVMe storage pool, this appears to be another excellent and working solution.

Links: 

https://www.asmedia.com.tw/product/249yq0aSx7zRFGJ9/7c5YQ79xz8urEGr1 

E-Bay Sample Link 

Turkey Link 

Amazon Turkey 

Images:

I hope this additional information proves useful to the community.